A flash memory-based solid state disk (SSD) is implemented using a semiconductor memory device, and accordingly it is possible to access data at a very high speed in comparison to a hard disk. With the development of SSD-related technologies of manufacturers, SSDs are being used in various fields, such as cloud computing systems or file systems, today due to durability and stability of SSDs.
However, since overwriting is not possible due to characteristics of materials in flash memories that are the base of SSDs, writing needs to be performed after input data is erased. Due to the above issue, it is impossible to maintain constant performances of SSDs.
According to a related art, a scheme of isolating internal resources managed by an SSD for each virtual machine (VM) has been used. However, in the related art, when pages of different VMs are included in a block of the SSD, and even when a garbage collection (GC) is caused by a specific VM, a time is required to manage pages of the other VMs.